Early settlement dynamics in the Pacific revealed through ancient DNA

The ancient DNA analyses of human skeletons from western Remote Oceania are providing new insights into the complex history of settlement in this vast Pacific region over the past 3,000 years. The region, encompassing major island groups such as Vanuatu, New Caledonia, Fiji, and Polynesia, is home to societies with remarkable linguistic and cultural diversity.

An international research team, led by Professor Cosimo Posth from the Senckenberg Centre for Human Evolution and Palaeoenvironment at the University of Tübingen, has traced the major human migrations that shaped the diversity of these islands. By examining 72 ancient human remains spanning the past three millennia, the team has determined the chronology of migration waves with greater precision than ever before.

The study, published in the journal Cell, reveals that the first Remote Oceanians arrived in the region around 3,000 years ago, following one of the greatest human expansions into the open ocean. The first wave of settlers, primarily derived from a Southeast Asian source population, spread more rapidly than the later Papuan-related migrations.

While Papuan-related ancestry is detected as early as 2,700 years ago in Vanuatu, it takes another 500 years for this ancestry to be detected in Fiji. The study also uncovers the genetic history of Polynesian outlier communities in Vanuatu, which maintain Polynesian cultural and linguistic features despite being outside the Polynesian Triangle.

Direct evidence suggests that these communities were established around 1,000 years ago through migration from Polynesians. Additionally, a 1,500-year-old community in Fiji exhibited uneven distribution of recent Papuan-related ancestry, with a distinct biological kin group that may have practiced social strategies to maintain wealth or social status.

Overall, the new study sheds light on the major migrations and social interactions involved in the settlement of western Remote Oceania.